2-[2-Phenyl-2-(2-pyridyl)]ethyl-2-imidazoline (hereinafter referred to Compound A) is known to have a hypoglycemic activity (U.S. Pat. No. 4,138,491), an inhibitory activity on blood platelet aggregation (U.S. Pat. No. 4,138,491), and a therapeutic effect on retinopathy (Japanese Patent Application (OPI) No. 194020/86 (the term "OPI" as used herein means an unexamined published Japanese patent application)), but has not been reported to have an effect for treatment of asthma.